歙县南部的十九万亩土地上实行一年三熟套种輪作制,一般年产量在五百至七百斤,高于当地旱地、水田的两熟栽培。它的套种輪作方式很多,归納起来有三种类型:一是小麦——大豆——玉米;二是小麦——大豆——粟;三是蚕豆——大豆——玉米(或粟)。以第一种类型最普遍,面积約占三熟制的85%以上;第二种类型只占10%左右。小麦——大豆——玉米的套种輪作方式是:单行小麦行距一点八尺左右,于小麦拔节、孕穗期的“清明”前后,在行中套两行彼此靠攏的六月大豆;“小滿”前后小麦陆續完熟,大豆已到初花期,这时再靠小麦边套种中熟玉米;“霜降”后“立冬”前玉米还在成熟阶段,就在玉米行間套种小麦。值得提出的是,群众总习慣先种玉米,然后再割麦,目的是使玉米能早播,使玉米苗在大豆封壠前赶上大豆苗高,以免遮阴影响生长。小麦——大豆——粟的 Lixian southern region of 190,000 acres of land to implement three-year intercropping crop rotation system, the general annual output of 500 to 700 pounds, higher than the local dry land, paddy field cultivation of two crops. There are three different types of rotation: wheat-soybean-corn; wheat-soybean-millet; and third, broad bean-soybean-corn (or millet). The first type of the most common, the area accounted for more than 85% of three cooked system; the second type accounted for only about 10%. Wheat - soybean - corn intercropping rotation method is: one row of wheat row spacing of about eight o’clock, at wheat jointing, booting stage of the “clear and bright” before and after the line set in two rows close to each other June soybeans; “Xiaoman” Before and after the wheat gradually matured, soybean has reached the first flowering, then rely on wheat intercropping medium maturing corn; “frost down” after the “beginning of winter” before the corn is still mature stage, interplanting wheat in the corn line. It is worth mentioning that the general public first habit of corn, and then cut the wheat, the purpose is to make corn can be sowed early, so that corn seedlings in soybeans before catch up soybean seedling height, so as not to shade affect growth. Wheat - Soy - millet